Read Dorminey, Bruce, “Dark Threat”, Astronomy, Vol. 33, No .7, July 2005, pp.40-45 and Peck, Michael, “Defending Earth”, Aerospace America, Vol. 55, No. 2, February 2017, pp. 42-47.

1. Are the authors optimistic or pessimistic when it comes to impacters striking the Earth and prompting a global catastrophe?
2. How do the impacters in “Dark Threat” different from those in “Defending Earth”?
3. What do the authors feel can be done to protect Earth if such an occurrence is imminent?
4. After reading the articles are you more concerned, less concerned, or have an unchanged opinion regarding the threat of other celestial objects that have trajectories that coincide with that of the Earth?